The invention relates to a hair-removing device provided with a laser source, an adjustable laser beam manipulator for positioning a laser beam supplied by the laser source during operation in a target position on a skin to be treated, and an image sensor for detecting an image of at least a portion of the skin.
A hair-removing device of the kind mentioned in the opening paragraph is known from U.S. Pat. No. 5,653,706. The known hair-removing device is designed for use by a professional therapist and may be used not only for removing hairs but also for other dermatological treatments such as the treatment of necrotic skin tissue, varicose veins, or pigment spots. The image of the skin detected by the image sensor is rendered visible to the therapist on a picture screen. The known hair-removing device further comprises a control member by means of which the therapist can operate the laser beam manipulator and can thus guide the laser beam supplied by the laser source manually over the skin under treatment. While being guided over the skin, the laser beam has only a comparatively low energy density, and the therapist can monitor the position of the laser beam on the skin by means of the picture screen. When the laser beam is in the target position as determined by the therapist, the laser beam can be intensified for a predetermined time duration by the therapist through the operation of a further control member of the hair-removing device. The laser beam has a wavelength which is well absorbed by the tissue to be treated, so that the tissue present around the target position is strongly heated locally by the laser beam, and the relevant tissue dies. For a permanent removal or epilation of a hair present on the skin, the laser beam is aimed at the root of the hair, so that the root and the tissue surrounding it die. Since the known hair-removing device is provided with said image sensor and adjustable laser beam manipulator, it is possible to treat the skin locally with a laser beam of a comparatively small spot diameter, so that the laser source need have only a comparatively low power. Accordingly, a comparatively small and simple laser diode is used in the known hair-removing device.
A disadvantage of the known hair-removing device is that a comparatively long treatment time is necessary for the removal of all hairs present on a skin under treatment because the therapist must displace the laser beam manually from one hair to the next. In addition, a determination of the target position of the laser beam on the skin requires the user to have a considerable experience, so that the known hair-removing device is suitable exclusively for use by a professional therapist.